Help me find a replacement to this transistor please?

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Help me find a replacement to this transistor please?

Postby Joshua_S » Fri Mar 16, 2018 10:55 am

Hi guys,
First time posting here :D I got a 7800 the other day as is untested and it has this problem. When you plug it in, it turns on and doesn't turn off. I read somewhere online that it may be from a bad Voltage Regulator. When I opened it I saw a weird yellow gel-like substance mixed with a black crusty substance as seen on the RF shield.
Upon cleaning the shield it was badly corroded. This substance also corroded the board, most of the damage being done to the component labeled "MJE 210 9 732"
I looked it up, and check out some info relating to this such as What is Transistor and Its Functions and Characteristics,
then it would seem that (correct me if I'm wrong) this component is a transistor that holds the current power state. I believe that replacing this component will solve my problems. Where can I find a replacement that will work?

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Re: Help me find a replacement to this transistor please?

Postby Benj » Tue Mar 20, 2018 1:25 pm


The weird yellow substance could be from one of the electrolytic capacitors, they can explode or leak and are notorious for causing problems. You may need to replace your electrolytic caps rather than the transistor.

If it is the transistor then I think these may be compatible. ... ord=MJE210